New Type of Electron Emission from a Gold Surface Induced by a Strong 4 NS CO₂ Laser Pulse

Abstract

In recent years, there is a renewed effort in understanding the physical processes of the interaction of strong short laser pulses with metal surfaces. These processes are very interesting from both academic (fundamental questions of intense field QED) and practical (material microprocessing) points of view. Many review papers have been published on both of these subjects [l, 2]. It is already knowm both theoretically and experimentally that with laser pulses of short wavelengths (e.g. ruby and Nd-glass lasers), multiphoton interaction governs the photo-electron emission process [11. If a long wavelength laser pulse is used, (such as a CO₂ laser, λ = 10.6 μ), theory [3, 4] predicted some quite new phenomena, (e.g. optical tunnelling). Therefore, using an intense CO₂ laser pulse, strong deviation from the multiphoton process is expected similar to the case of ionization of an atom which will be presented also in this conference by us.

On leave for the academic year 1982–83 from the Central